Reclaiming system in a sulfite pulp process.



G. B. THORNE. 'REOLAIMING SYSTEM IN A SULFITE PULP PROCESS".

APPLICATION FILED AUG. 31, 1912.

Patented 0ct.21, 1913.

wi bneoeo cant B. THORNE, or HAWKESBURY, on'ramo, CANADA.

BECLAIHING SYSTEM IN A SIU'LFI'I'E PULP PROCESS Specification of Letters Patent.

Application filed. A lg'lst 31, 1922. Serial mi. 718,134.

- To all whom it may OOQ'BGEWFB.

Be it known that I, CARL Bunsen THORNE, a subject of the .King of Norway, and resi dent of Hawkesbury, in the county of Prescott, in the Province of Ontario, in the Dominion of Canada, have invented certain new and useful Improvements in Reclaiming System in a Sulfite Pulp Process; and I do hereby declare that the following is a full, clear, and exact description of the same.

The invention relates to improvements in a reclaiming system in a sulfite process, as described in the present specification and illustrated in the accompanying drawings that form part of the same.

The invention consists essentially in the novel means employed, whereby the strength of the acid liquor prepared for carrying out the sulfite process is materially augmented by the utilization of the gases from the digester in a particular manner.

The objects of the invention are to lessen the consumption of sulfur, to providev a good strong liquor for the work and thereby improve the means of carrying out the sulfite process and generally to devise a simple cheap and efiicient means of saving sulfur from Wasting. is

The drawing is a diagrammatic view showing a suggested arrangement of the plant. I v

In this system the present means of obtaining the acid is the same, as far as the burning of the sulfur and the cooling of the gases from same;

In the accompanying drawing 1 is the sulfur burner, 2 is the gas cooler 3, 4 and 5 are the pipe connections .from the said burner to the cooler. The cooled gases rise mto the pipe 6 and from there are driven by the fan 7 into the tower'8, though it must be understood that a tank or other receptacle may 'be used in place of the tower. In the tower 8 a grating 9 extends in an inclined direction above the inlet from the pipe '6 and supports a quantity of limestone 10 inbroken pieces. The tower 8 has an' exhaust pipe 11 extending therefrom through the top for the exhaust of ases not utilized and a water inlet 12, whic is connected by a pipe 13 to a pump 14, preferably below the tower, said pump 14 driving'water from the water receptacle 15 up through the pipe 13 and through the water inlet 12, said water percolating th ough the limestone pieces 10 and meeting amid absorbing the gases rising from ,grating which the return gases flow steadily from below, said gases acting on the limestone and making with the falling water the' cooking liquor. The liquid thus formed drops to the bottom of the tower 8. This liquor thus obtained flowsthrough the outlet 16 and is driven by the pump 17 and through :the pipe 18 and into the tower 19 through Patented 0a. 21, 1913.

the inlet 20. The liquor falls by i av it-y 4 down interior of the tower 19 an is delayed' by the pieces of wood 21 or other mateiial, the said wood being of such nature as will not readily =be destroyed by the liquor. The wood 21 is supported on the 22 above the gas inlet 23, through the pipe 24, said gases meeting the down flowing liquorin the tower 19' and materially enriching it so that the solution in the lower end of the tower is-ready for use in the sulfite process and flows out through the outlet 25 into the storage tank 26. The

pump 21 through the pipe'28 and poured Previously the difrom the hopper 30. As soon as the requisite amountof liquor is poured into the diliquor in the storage tank 26. is raised b'y the gester, the cover 31 is closed and steam turned on through the pipe 32 and preferably into the elbow of the outlet pipe 34,

said outlet pipe being from the bottom of the digester and having a cut ofi' valve, which may be opened for-the drivingou't of the finished pulp. Y

.The digester 29, adjacent to the upper end thereof, has a gas exhaust opening, con trolled by the reliefvalve 3.6, into the ex turned on the circulation of acid is begun in the said digester and there will always be 'haust pipe 37,. so that when the steam is" gas accumulating at the upper end, which exhausts through the. pipe 37, being driven through by the pressure. of the steam, cer; tain quantities of which naturally escape with the liquor.

The exhaust gases and escaped steam flow through the exhaust pipe 37 to the separator 38, the liquid going to the bottom of said separator and the (gases passing on through the outlet pi e 39 to the cooling coils 40 and y from there owingthrough the pipe 24 into the tower 19 .as already explained. I The-- liquid in the lower end of the separator 38,

and which is comparatively weak, flows out through the outlet pipe 41 into and throughq the coolingcoils i2 and from there to the tank 43. The tank 43 is coiinected to the Water receptacle 15 by the pipe 44, therefore during the continuation of the making of.

the liquor, in place of plain Water being pumped up through the pipe 13 and into the tower 8 the weak liquor with water is driven up, so that the solution in the bottom of the tower8 is much stronger, than it would be' under ordinary conditions, in other words, it 10 has the benefit of utilizing all the weak acid from the digester thereby gaining the last bit of strength from the sulfur which would be otherwise wasted leaving only the burning of the sulfur and the cooling of the gases.

golng to the. towerascommon practice.

It must be understood that the drawing accompanying this specification is merely diagrammatic and does not point with any finality, as to the form or particular arrangement of the plant, it being merely to assist in the understanding of this description, therefore anything in the specification which specifically refers to and describes a part of the arrangement of the plant must be treated broadly and only limited by the scope ofthe claims forfnovelty'following.

What I claim is I y 1. A reclaiming system in asulfite process, comprising separating means for the cess, comprising separating means for the vapors exhausting from a digester, means for condensing the separated vapors, means for cooling the condensed vapors, and means the cooking mixture, one receptacle being connected to said pump at, its upper end, and the other at its lower end being con- Itected to said condenser.

3. In a reclaiming system in a sulfite process, a separator having a gas outlet towardthe upper end thereof, a liquor outlet at the lower end thereof and a fluid inlet connected to the upper end of a digester, a condenser connected ,to said gas outlet, a cooler connected to said liquor outlet, a pump connected to said cooler and means for making the cooking mixture formed of two receptacles, one of said receptacles'being connected at its upper end to said pump and the otherof said receptacles at its lower end to the said condenser. Signed at the city of Montreal, Quebec, Canada this 6th. day of August 1912 CARL B. THORNE. Witnesses: 1

HARRY DAVIS, M. PATENAUDE. 

